Hand and indicator for watches and like articles



wncumz. HAND AND INDICATOR FDR WATCHES AND LIKE ARTICLES.

APPLICATION FILED OCT. 14. I921.

1,416,176. Patented M y 16,1922;

INVENTOR.

M? a I UNITED srarss PATENT i HERMANN 1*. 01mm, or HARTFORD,cominc'rrour, ASSIGNQR To -AMERICAN RADIUM COMPANY, on NEW YORK, N. Y.,A CORPORATION on NEW onx.

HAND AND INDICATOR FOR WATCHES AND LIKEiAIUIICLILS.

To all whom it may concern i Be it known that I, HERMANN F. CUNTZ, acitizen ofthe UnitedStates, resident of the city of Hartford, county ofHartford, and State'of Connecticunhave invented certain new and usefulImprovements in Hands and Indicators for Watches and like Articles, ofwhich the following is a specification, reference being had to theaccompanying drawings, illustrative of particular embodiments ofmy'invention, this being a division of my application Serial No.482,095, filedJuly 2, 1921, allowed October 3, 1921.

This invention relates to indicators such as the hands of clocks,watches, gauges, meters and other devices, and instruments, and for likeor similar devices, as may appear fromthe' following specification.Particularly in such indicators the inventionrelates to providing themin a form or construction permitting advantageous equipment withluminous material, so that the indicators or hands may be readilyvisible and readable at night and at the same time affording accurateand easy reading or readily discerning of an indicator or indicators andtheir position withrespect to graduations by outside light such as bydaylight orwhen visible by ordinary illumination. a

The application of luminous material involving compounds of radio-activeandradi0-responsive material, has heretofore been practised by embodyingsuch permanently luminous compounds in a recess in the hands 1 ofinstruments and particularly in. watch and clock hands so that asuflicient bulk of the material is held spread over a suflicient area toprovide an amount of luminosity to anextent and for a suflicientdistance'suitable for the particular instruments or case involved; or insome cases the permanently self-luminous compound is spread over thesurface of a: hand with suitable protective covering to keep it inplace. A reasonable area is required with a considerable width withrespect to the length in a line intended to be luminous in the dark,sufficient to pro vide visible luminosity at a distance of a foot orseveral feet or yards,depending Speeification of Letters Patent.Patented Ma 16 1922;

Original application filed July 2, 1921, Serial No. 482,095. Divided and14, 1921. Serial No. 507,743. I

upon the particular use to which the permanently illuminated article isadapted. In view of the relatively larger width of line required forthis darlrtime luminous effect, the indicator, hand or pointer are of agreater width than permits accurate reading in the daytime or underconditions of ordinary outside illumination. It, therefore, becomesaproblem to provide such devices with permanently luminous material in amanner whereby accurate reading of the time or accurate reading ofinstruments, as to; the registration of pointers with graduations, canbe assured or in any event can become a matter of greater accuracy thanhas heretofore been the case by day and night. I i i In the case ofpointers or indicatorsand hands for watches,a broad surface 'coveredwith radio-luminous material, backed up by a relatively dark backgroundinvolves all the inaccuracy incident to, a broad line compared with avery fine hair line or narrow marker which should be used in ordinary orfull illumination for accurate determination of calibrationregistration. I, therefore, provide a pointeror hand with surface of arelatively suilicient widthcto carry'an ample area of radio-luminousmaterial for the desired degree of visibility in the darkness, but Iprovide medially orin the axis of such a pointer or hand, a narrowcontrasting line of non-luminous material and of contrasting color withthe luminous ma; terial in the daytime or when subject to out sideillumination. Such central line of nonluminous material provides foraccurate reading in the daytime and the provision of such a line whetheron the pointer, calibration,marking or numerals, supplements thisapplication filed October the art heretofore known by giving to the useof radio-luminous compound on instruments and other devices an assuranceof accuracy for ordinary reading by outside light which has notheretofore been the case.

The subject-matter of this application involves hands or indicatorsreadable in the daytime as well as the dark which have particularstructural advantages, and may be selt-luminized part of their lengthand structurally improved in other parts, as will hereinafter appear.

Emboeiments oft my invention are shown in the accompanying drawings inwhich:

Fig. 1 is a plan ViO\V ot a pointer or hand constructed to holdradio-luminous material on, a portion of its length with. the othernon-luminous portion structurally eooperating for advantages invmanuttacture, durability and strength, or otherwise.

Fig. 2 a side elevation of the pointer or hand shown in Fi 1.

Fig. 3 is a plan View of a similar pointer or hand slightly modified asto the day and night reading; parts.

Fig. 4 is a cross-section of the seli-luminous portion of the pointer orhand as shown on the other figures.

As shown, the hand orpointer is of thin material such. as steel or othermetal, and has the material at the hub a pressed to form a channel forpart of the length adjacent to the hub with the top side N and with thelateral flanges N; Approaching the other end of the hand, the strip isdepressed. or, conversely, ridge 0 is crimped or pressed up to the levelof the surface N, forminga metal ridge preferably in. the centre oraxis, that is in a line radial to the centre of the hub. This ridge Oruns to the tip a, as shown inv Figs. 1 and 2, or to such extent as maybe desired for any particular case with reference to the arrangementshown of the tip structure, as, for example, shown in Fig. 3, orotherwise. In Fig. 3, the ridge 0 extends through the major part of the'adio-luminous field Q, but not to the tip a, there being}; lateralflanges C-C flanking the tip, which term means of more seeurely holdinga desired coating of radioluminous compound at the tip without its axisbeing interrupted by the medial ridge.

Thus tl c halt of this torm of handy or pointer nearer the outer end hason its up per surface recesses such as (a), of a siiiilicicnt area. toaccommodate an amount of radioluminous material suilicient to assurevisi bility in the dark. .he ridge 0 extends the stiflness oi thechannel portion ll-N, to the very tip, or as far as may he desired,while providing, recesses on either side ot the medial ridge toaccommodate the selt-lun'iinous material it provides a structure thatdoes not increase the thickness of? the hands beyond the thickness ofthe portion near the hub or what may be required for strength in suchparts. i

It will thus be seen that the constructions described provide a ridge orridges intermediate the side edges of a hand or pointcr, which aid tosecure, and which can. serve to assure uniform thickness of the'radio-lui'ninous material applied to the surface of the base. lurthermorc, the ridge of rigid material forms the upper limit; of thehand structure with the base at the bottom, so that both top and bottomare protected during the operation oil? the hands or pointers againstinterfering objects which might otherwise dislodge the radio-liuninousmaterial in the absence oi the protecting ridge. T he structure alsoserves to accommodate most advantageously the application ofradio-luminous material. in different ways, as, for example, theprincipal ingredient, namely, the radio-respoi'isive material may bevery quickly applied to hands of my construction, because the ridge inits various arrangements serves to control the thickness and assure theehiciency of the application of material. either in base or other termwith entire uniitormi 1:3 throughout the length of the hand which it isdesired to cover; there alter the radio-active material of tar lesserrelative quantity may be readily dusted onto the surface or sprinkled onto the radiomesponsi to or sub-eompoimd, as it is sometimes called. Andin any finishing operations the manipulation of the tools will besubject to the control of the ridge in conjunction with the lateralborders of the hands, whereby unifiiirmity o't finish with economy inthe operation is a result of great advantage from manutacturiug orstudio work standpoint.

It will also he realized that a narrow line provided in the structure ofhands or dials as heretofore described, as well as many modL ticationsthereof, supiiilies a daytime yisibility of a fine hair line which mayhe so narrow that it will in no way interfere with the luminosity indarkness oil? the adjacent radio-luminous areas. The light emission fromradio-luminmis areas is such that with a total area, and with a width ofluminous line in proportion to its length, sufficient tor the desiredlegibility in the dark for a watch or clock or any other particular use,means that such light emission will have substantially the value of theentire area of the hand or figure, and tor night observation the narrowuncoated central ridge will not appear, i. e., it will practically hebridged by the light emission, from the adjacent luminous areas.

onrersely, hands or figures constructed and termed as heretoforedescribed may he ol" white or light tints matching the adjarcnt enamelcolor of: a dial umlerlying the hand. in which cases watches or clockswith their reading parts so constructed will hare in daytime asubstantially invisible breadth oi hand, but a narrow clearly visibleline, even a hair line, will constitute the central, indicating orreading marking: for the hand and for the dial marking or figure withjustas great accuracy for daylight use as any o'dinary watch, clock orother indicating ,i to

device,and with no apparent increased breadth in the markings or handsduring daytime reading. The embodiment shown in the accompanyingdrawings is particualso to the very tip. In structures heretofore used aluminous dot has been placed midway between the tip and the hubaffording no directional vision aid, and also leaving a bare pointer.forming a long sec tion of the tip entirely devoid of radioluminousnight reading area. I i i The revolutionary development "involved in theintroduction of readable-in-the-dark watches, clocks, compasses andother indicating instruments and devices, is well known to have involvedat first the serious objection of makingvery broad hands and eitherlarge dots! for graduations or broad figures in order to provide asufficient area so that the permanent self-luminosity or radio-luminousmaterial would serve the night reading object. The clumsiness of suchstructures impeded for yearsthe more general adoption of the day andnight reading-parts of timepieces and other instruments, and thenecessity for providing means so that the same night visible instrumentswould be ac curately, readable by day, led to the provision of a border,or more properly two borders, one on either side of the self-luminousarea. Such borders on broad hands were an initial objection criticisedas clumsiness, which the general usefulness of the self-luminousmarkings has but vpartially overcome. Initial attempts in the case ofsome instruments led to the use of a contrasting background, so that thewhite hand was bordered by a dark background but this only made dayreading relatively visible but still involved the broad and inaccuratemark which is white for dayreading and has the same objections for manyclasses of timepieces as well as other devices. Added to the solution ofthe problem of producing reading parts of timepiecesor other deviceswhich can be accurately read in the daytime, it will be seen that thestructures heretofore described have many added advantages, such asassuring uniformity in the amount or depth of the coating ofradio-luminous material, and stiffening the pointers and permit-ting theuse of the thinnest obtainable sheet material for the base of hands orpointers in order to'reduce the total thickness of the hands as well asto provide uniformity throughout the length of area of the luminoussurfaces. Other advantages will be appreciated in the practice'of' thisinvention, facilities formanufacture, as well as economies and speed ofproduction with uniformity of product, add to the value and durabilityand other characteristics of the finished product.

While various modifications may be made in the structure and arrangementas well as the material and use of the articles, of which specificembodiments have been heretofore.

described, I do not confine my invention to the specific forms shown inthe accompanying drawing and herein specified in detail, but what I'claim and desire to secure by Letters Patent is: y

1. An article of the character described comprising a base flanged fromthe hub for a portion of its length and having a ridge.

extending the remaining portion through the axis to form lateralrecesses on either side and radio-luminous material embedded in saidlateral recesses below the planeof the top of the ridge.

2. A hand or indicator for watches and like articles, comprising a metalstrip with a channel section forming the portion from the hub part ofthe length, and a radial ridge extending the major part of the remaininglength of the hand, flat areas on either side of said ridge andradio-luminous material co'ating'said side areas to a depth notexceeding that of the ridge.

3. A hand or pointer of the character de scribed, comprising anon-luminous portion extending from thehub part way toward the tip, aliuninous area of greater width forming the remaining length of the'handto the tip, a non-luminous medial line on said luminous area. i

4. A hand or pointer for the purpose de scribed, comprising a stifi'enedsection adja cent the hub and a ridged section contiguous theretoextending toward the tip, of a thick ness not exceeding the firstsection, integral base portions on either side of said ridge andradio-luminous material secured between said ridge the ridge.

5. A hand or pointer for the purpose deand bases to a depth notexceeding scribed, consisting of a thin sheet metal hav ing two ma orportions, one portion having means for transverse stiffening, and theother portion havin a radial luminous field of greater length t an widthwith a nonluminous line through said radio-luminous field in a directionradial from the hub centre of the hand.

6. A hand or pointer for the purpose described, consisting of a thinsheet metal having two major portions one portion having means fortransverse s t-ifiei'iing and the other portion hzwing a radial luminousfield of greater length than Width, a medial nonluininousj line axiallyin said field and a non luminous border atone end 01 said field.

In testimony whereof, I have signed my name to this specification, inthe presence of two subscribing witnesses, this 11th day of October,1921.

HERMANN F. CUNTZ. VVitnesSes:

ROBERT E. LICGAGUE, JAMES M. OARPLES.

